Could I safely use copper sulfate in my swimming pools as an algaecide?

Question

I used cupric sulfate as an algaecide in my swimming pool for a while without problem. I was adding a very small quantity of it (one teaspoon when the season start and 1/4 teaspoon whenever I add water.) However, a "swimming pool expert" told me I should not, that it is dangerous, and various others claim (Obviously, he wanted to sell me his own algaecide). I had many problem this year to keep my swimming pool clear of algae, So I'm considering returning back to cupric sulfate.

So, I made my own search and this use copper sulfate seam quite controversial:

Some say it is ok
Some say dont use it
Some say maybe
Some are even more confusing

Does someone has an objective notice for that?

score 3 · Accepted Answer · edited Sep 08 '11 at 13:58

3

As with any chemical, it depends on the amount. Overdose and you'll not be very well off. Check the volume of your pool and keep it below 1ppm.

The EPA limit for copper sulfate in drinking water is 1 ppm. This limit has been set to prevent a disagreeable taste from copper in drinking water, as well as to provide adequate protection from toxicity.

edited Sep 08 '11 at 13:58

DavRob60

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answered Sep 08 '11 at 00:21

Will it work as an algaecide at those levels? – Oddthinking Sep 08 '11 at 00:31
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apparently 0.25tsp / swimming pool worked for him. Olympic sized pools are 2,5000m^3 so 0.25tsp would be about 0.05ppm, which is below the legal limit. It depends on his swimming pool volume, which he doesn't specify. – Sep 08 '11 at 03:06
I got a 30 000 liters pool. So, if I calculate correctly, the 1ppm limit is about 30 gram (6 teaspoon), right? – DavRob60 Sep 08 '11 at 12:11
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Remember, this isn't drinking water. The limit for chlorine in drinking water is 4ppm, but I've been in many a pool with much higher levels than that. Still, you'll want to keep it (the level of copper sulfate) around .5ppm, otherwise peoples hair will start turning green. – Satanicpuppy Sep 08 '11 at 14:35
@Satanicpuppy 0.5ppm copper will turn hair green? Sounds like time to ask a question... – Nick T Apr 26 '12 at 19:53

score 3 · Answer 2 · answered Sep 12 '11 at 17:13

Health Canada said it's OK, but they don't say anything about the recommended concentrations except to refer to the label directions :

Health Canada has found that using copper sulphate-based algicides in swimming pools presents no significant danger to bathers. When used according to the label directions, copper sulphate algicide should not cause skin irritation for bathers. However, label directions should be carefully followed when handling undiluted copper sulphate-based products to reduce the potential for skin irritation.

Could I safely use copper sulfate in my swimming pools as an algaecide?

2 Answers2